Premium
Inhibitory effect of melatonin on platelet activation induced by collagen and arachidonic acid
Author(s) -
Kornblihtt Laura I.,
Finocchiaro Liliana,
Molinas Felisa C.
Publication year - 1993
Publication title -
journal of pineal research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.881
H-Index - 131
eISSN - 1600-079X
pISSN - 0742-3098
DOI - 10.1111/j.1600-079x.1993.tb00501.x
Subject(s) - melatonin , platelet , arachidonic acid , medicine , endocrinology , chemistry , epinephrine , pineal gland , cyclooxygenase , adenosine diphosphate , adenosine , inhibitory postsynaptic potential , platelet activation , platelet aggregation , biology , biochemistry , enzyme
Melatonin, an indolamine synthesized in the pineal gland, is known to have antiprostanoid activity. The inhibition of platelet aggregation induced by melatonin has been proposed to take place through the cyclooxygenase pathway. In the present study, we found that melatonin has a marked inhibitory effect on collagen, arachidonic acid (AA), adenosine diphosphate (ADP), epinephrine, and A23187‐induced aggregation in platelet‐rich plasma. On the other hand, using metrizamide‐filtered platelets resuspended in Tyrode's buffer, melatonin fails to suppress AA‐induced platelet aggregation and 14 C‐5‐HT release. Under the same conditions, melatonin inhibits collagen‐induced platelet activation; however, the addition of threshold doses of AA (0.3 mM) abrogates this effect. These studies suggest that melatonin also inhibits platelet function at a stage preceding the cyclooxygenase‐dependent pathway.